Method of making axle housings



April 25, 1933. E. B. CLARK METHOD OF MAKING AXLE HOUSINGS Filed April 9, 1928 3 Sheets-Sheet l I I 1 I I I I I I l I I I I I I 1 I U I v I I I I I I I I I I I I I I I hmsvzfor B CLARK METHOD, OF MAKING AXLE HOUSINGS a Sheets-Sheet 2 Fi ledjpril 9, 192a Apr]! 25, 1933. CL 1,905,150

METHOD OF MAKING AXLE HOUSINGS Filed April 9, 1928 3 Shee ts-Sheet 3 j fzz'rerzi or fz zyerze 5 (Ya/A Patented a... 25, 1933 UNITED STATES PATENT OFFICE EUGENE B. CLARK, OF BUCHANAN, IICHIGANQ ASSIGHOB 1'0 cum GOIPAII'TL, OI BUGELHAI, IIGIIGAN, A OORPOBLTION IIGIIGAI men or mum axm riousmes Application fled April 9, 1988. Serial I0. 868,5.

My invention relates to the manufacture of rear axle casings and the like and discloses and claims a particular method ofmanufacture and resulting structure of the general method and structure disclosed and claimed in the copending ,application of George Spatta, Serial No. 416,537, filed December 26, 1929.

I am aware that it has heretofore been proposed to form rear axle casings from wrought'tubing by slitting the central art of the tube and spreading the same to orm an open banjo frame. Heretofore the formation of a rear axle casing from a piece of seamless tubing or the like has resulted in a structure of undesirable characteristics, one feature of which has been the difierence in thickness between the banjo frame portion and the arms on each sideof .it. If a piece of tubing heavy enough to make the ban'o frame isemployed as t e blank, then shrin ing of the tubing at the ends to bringit down to the proper size for the arms of the axle increases the wall thickness to an undesirable extent. For example, if a piece of tubing having a wall thickness of of an inch is em loyed the ends or arms ofthe axle will be thickened to approximatel of an inch, which is thicker and heavier an necessary. Such. unnecessary weight on the rear axle involves needless initial expense and "ishighly undesirable from an operating.

standpoint and should be avoided.

According to the present invention I am able to' form a rear axle casing in which the relative thickness of the arms and of the banjo frame is under control so that the desired form and strength without surplus weight can be produced. This control I secure by treatment of the tube prior to slitting and forming.

While theoretically it might be possible to thicken the walls of the tube or banjo frame after slitting or slotting the tube, in practice this is not feasible because as soon as the tube is cut longitudinally its hoop strength is one and control of the metal is lost.

start with a'tube of suitable diameter 50 and length but of relatively wall. The diameter of the tube is preferably smaller than the diameter of the banjo frame and larger than the desired diameter of the arms. The thickness of the wall of the tube which I employ is such that shrinkage of the diameter of the arms results in the desired wall thickness of the arms. The desired thickness of wall at the central part where the banjo frame is formed is secured by initial upsetting before slitting. After the proper stretching and 'formin of the central part of the tube to provide the ban'o frame, the wall of the banjo frame will of the desired thickness, namely substantially that of the finished arms. Obviousl within limits any desired relation of we thickness and/or diameter may thus be eecured. Preferably I emplo seamless tubing so that no weak s ots or aws will be contained in the resu ting structure, but obviously. butt or lap-we d em loyed.

n the forming of the banjo frame the walls on each side of the slotted portion are spread out sidewise substantiall strai ht so that they form virtuall tubu ar wa at right angles to the axis 0 the original blank. Then by inserting stretching dies on the inside and a contractin die on the outside these walls are form into a transverse c lindrical banjo frame with inturned ange's parallel to each other and to the a longitudinal axis of the blank.

The ends of the arms are preferably upset and expanded, or may otherwise be formed in a variety of wa s to provide a bearingseat or housingand a rake plate.

Now in order to acquaint those skilled in the art with the manner of practicing my invention I shall describe in connectlon with the accompanying drawings typical steps resulting inthe novel form of axle casing embodying my invention..

In the drawings Fig. 1 is a side elevation and Fig. 2 an end view of the blank, which is. a piece of seamless tubing. I

' Fig. 3 is a side elevational view and Fi 4 an end view of the blank after the operation of u tting the central part of the tube and thic g the walls of the same.

ed tubing could be factors of a specific form of axle casing, I do Fig. is a side elevational view and Fig. 6 an end view of the blank after the operation of slotting the central part.

Fig. 7 is a side elevational view and Fig. 8 an end view of the blank after the operation of reducing or shrinking the arms on each side of the center. i

Fig. 9 is a side elevational view and Fig; 10 a transverse cross section of the blan 10 after the operation of opening up the slotted central portion.

Fig. 11 is a side elevational view and Fig. 12 a. transverse cross section through the banjo frame, showing the axlehousing with "the completed central banjo frame.

Fig. 13 is a side elevational view and Fig. 14 an end View of the completed axle casing after the upsetting and expanding of the ends of the arms to provide the bearing seats and v 2 flanges for mounting the brake plates.

Fig. 15 is a fragmentary longitudinal section through a Modified form of axle casing in which the end of the arm is expanded out and then collapsed to provide a flange for 2 the brake plate and a seat for the bearings.

Fig. 16 is a side view of a modified form of end of the axle casing; and

Fig. 17 is a cross section of the casing shown in Fig. 16. Referrin now to Figs. 1 and 2, I employ Hi It typica practice of my process a seamless steel tube 1 about 55 inches long, 4% inches in diameter and having a wall section of an inch thick. While I refer to the above dimensions as explaining the manunot intend by these dimensions to limit the invention but merely to explain a specific Way in which the invention may be carried out.

This length of tubing is heated and is then provided with an internal mandrel and subjected to upsetting pressures so that the Walls along the central part which are softened by heat are thickened as indicated in Figs. 3

and 4.

A die is employed to control the extent to which the wails are increased in'thickness throughout this portion which is required toform the banjo.

While 1 have described the wins .5 increased in thickness by spreading outwardly,- it is to be understood that I may, if desired, restrain the metal from flowing outwardly 5 and cause it to flow inwardly instead, but in the preferred practlce of my inventlon I maintain the inner diameter substantlally uniform and thicken the walls outwardly along the central portion, as indicated at 2- in Figs}; and l, for the purpose of providing the desired thickness in forming the bano.

Thereafter, as shown in Figs. 5 and 6, the central part is slotted longitudinally as inso dicated at 33 in Figs. 5 and. 6, this operaand since sufficient material is present because 11 and 12 by tion of slotting beingfperformed b the use of a suitable horn die and punch. ile I have shown the central part of the blank as slotted by a relatively large ,slot'or opening, it is to be understood that by the term slotting I intend to include also cutting the walls ongitudinally which is often termed slitting. I prefer to cut the slot to permit the entrance into the opening of a suitable spreading die,

of the initial thickening or upsettin operation as indicated in Figs. 3 and 4, tl qe work of spreading the banjo portion is facilitated, and the use of the relatively large slot is permissible because of the presence of suflicient metal at this central part.

After the slotting operation the blank is then treated to bring it to the form shown in Figs. 7 and 8 by shrinkin the arms or ends 44 by passing a shrin in die endwise over the end portions 5-5 0 Fig. 5 to bring the blank to the form shown in Fig. 7

wherein the thickness ofthe endsor arms 4-4 is substantially the same as the thickness of the walls 2 of the banjo portion 6.

The arms 4-4 are now shrunk; to approximately 3 inches in diameter, and they have a wall thickness of approximately of an inch, thereby providing a substantially uni form thickness throughout the entire length of the blank.

. It is to be observed that the central portion '2 which later becomes the banjo has tapering shoulders 7-7 (see Figs. Sand 5) and when the shrinking of the arms or ends 44 occurs the tapered tubular portions 8-8 are formed in a manner which merges the tapered wall thickness 7 into the tapering tubular walls 8 in such a, manner as to bring the thickness throughout the blank to substantiallya common value.

The blank shown in Fig. 7 is then subjected to a spreading action of the slot 3 to bring the blank to the form shown in Figs. 9 and 10 by flattening or straightening out 311) the walls 10-10. That is to say, the central part of the blank now has the walls 10-10 disposed transverse to the longitudinal axis of the blank in such a way as to define a transverse cylindrical opening 11, that is to say, consider the walls 10-l0 as symmetrical walls defining a part of the opening 11, the cylindrical Walls 10--10 merging mto the conical tubular walls 8-8 and being joined by webs or gussets ]2f12 on eachside, I which gussets are really a part of the tapered tubular walls 88. The attempt at this stage is to convert the cylindrical walls about the opening 3-3 as nearly as possible into a transverse cylinder intersecting and at right angles to the axis of the main body of the blank.

The blank shown in Figs. 9' and 10 is next treated to brixhgl it to the form shown in Figs;

e insertion of aninternal expanding punch over which there is brought an external contracting die. The forming of the opening 11 from the slots 3 can be performed by the use of an-internal expanding,

stretching die, which spreads the walls surrounding the slots 3 into sheet-like portions 10 defining the opening 11. In the transformation-of the blank from the shape shown in Figs. 9 and 10 to the form shown in Figs. 11 and 12 the internal expanding die stretches the walls about the opening 11 in Fig. 9, and

it will be seen that there would be a tendency to stretch and decrease the wall thickness of the gussets 12-12 on each side, but this tendency is counteracted by the folding inwardly of the edges of flanges 1313. While the gusset portions 12-12 are increased in their vertical dimension they are actually brought nearer together, and hence a surplus of metal from that operation permits the opening up or spreading to the shape shown at 1212 in Figs. 11 and 12. The flanges 13-13'are formed parallel and are spacedapart a distance which is approximately that of the outer diameter of the arms 4-4, al-

though this is optionaL; That is to say, the

' the maximum stress is at the central portion the increase in vertical depth and the highly advantageous channel section at the central portion provides ample strength in the resulting axle casing.

After the casing has been brought to the form shown in Figs. 11 and 12 it is desirable that suitable provision be made for mounting the axle bearings and brake plate, and there are several ways in which I do this. The preferred form is shown in Figs. 13 and 14. In this form I heat the ends of the arms 44 and upset and expand the same in one operation with a suitable punch and die, thereby forming on the end of the arm 4 an enlargement 16 terminating in a flange 17. This enlarged or expanded end 16 serves'to receive the hearing or outer bearing race for the axle of the rear wheel, and the flange 17 is adapted to.

receive and support the brake plate which is riveted thereto.

While in the form shown in Figs; 13 and 14 the ends are upset with the flange on the extreme outer end, it is possible to upset the end of the arm in a number of difl'erent ways to conform to the desired requirements of the rear axle and its bearings. For example, in Fig. 15'the arm 4 is first expanded or bulged out and then the bulge is flattened or folded back endwiseto form the flange 18 integral with the arm 4 and with the thickened end portion or housing 19 of an internal diameter larly along the ends of the arms 4 for the somewhat larger than the internal diameter of the arm 4 and with the walls thereof slightly thickened by upsetting.

The inside of the portion 19 may be of any ing race or bearing.

As shown in Fig. 16 the end of the arm 4 is upset and an integral solid flan e is formed as indicated at 20 to receive the rake plate, and outside of the-flange 20 another upset portion 21 is provided for receiving the bearmg race or bearing, and this ortion 21 may have formed integral therewit ears 22 which are finished b a slot out between them and through the a jacent walls of the portion 21.

The portion 21 and the ears 22 thereby serve as a split clamp to lock the bearing.

Whereas in t e prior description I have referred to the arms 4 as being cylindrical, that is, round cylinders, the casing may be reduced to a rectangulartubular shape particupose of attaching spring pads.

The manner of use of the axle casing will be obvious to-those skilled in the art. Suitable cover plates are secured to,the flanges 13 of the banjo frame 15 to house differential or other mechanism 'for connecting a propeller shaft to the axle sections which are housed within the arms 4-4, the bearings for which are provided at the outer ends of the arms 44, for exam 1c in, the enlargements 1616 of Fig. 13-. he axle casing may be employed in the construction of a rear axle such as is disclosed in the co ending applica tion of Edmund C. 'Mog ord, Serial No.

28,598, filed May 7th, 1925, issued January.

28,- 1930, as Patent No. 1,744,790.

It is to be observed that I start with a tube having walls thinner throughout than any of the walls of the finished casing. A part of the increase of thickness of the walls is secured by a preliminary upsetting and another part by shrinking of the diameter.

lVhile I have described the employment of a specific size and form of tubing, it is to be understood that my invention is not to be lim ited to the specific size and form as the invention is applicable to any size of tubing and to any reasonable increase in wall thickness, whether the said increase in wall thickness extends outwardlyor inwardly or partly in both directions. I, therefore, do not intend to be limited to the precise details shown, nor to the sequence of steps which I have above recited, as it will be apparent to those skilled in the art that these may be varied without dc parting from my invention. I

I claim:

1. The method of making an axle housing from a piece of seamless tubing which consists in upsetting the central part of a length of tubing toincrease the wall thickness thereof, slotting the central part of the blank for a suitable distance parallel with pur.

desired diameter to receive a suitable bearits axis and at diametrically opposite points substantially midwa of its len h, shrinking the ends of the lank to re uce the diameter thereof and to thicken the walls thereof, spreading the slotted ortion into transverse tubular walls, expan mg the central portion of said tube and folding over the edges thereof to form annular anges substantially parallel to each other and to the longitudinal axis of the housing.

2. The process of making an axle housing from a thin walled tube which consists in upsetting the central part of ,the tube to thicken the wallof the same where the banjo frame is to be constructed, slotting the thickened portion, spreading-the slotted portion and shrinking the diameter of the tube on each side of the slotted ortion. 3. A blank for axle casings comprising .a thin walled tube of a length approximately the length of a finished axle casing and having an integral upset portion, said portion having thickened walls providing suflicient stock to form a banjo frame and having diametrically disposed slots therethrough.

4. The method of making an axle casing which comprises upsetting and thickening the wall of a thin walled tubular blank along its central portion, cuttin diametrically disposed slots in said thic ened portion and shrinking the diameter of the end portions, simultaneously thickening the walls thereof.

5, In the method of making an axle casing from a thin tubular blank the process of thickening the wall of the tubular blank throughout, which comprises upsetting one portion of the wall of the blank and shrinking the diameter of another portion ofthe wall of saidblank.

. 6. In the method of makin an axle casing from a thin tubular bla the rooess ofthickening the wall thereof whic comprises thickening a part of the wall of the lank by endwise contraction and thickening another Portion of the wall of the blank by a circum rential contraction.

7.'The method of forming the outer end of a tubular axle casing which comprises upsetting and expanding the extreme outer end, forming an integral circumferential flange and forming a lug integral with the outer expanded end.

8. The method of making an axle casing from a thin-walled tubular blank which comprises upsetting the central longitudinal porneoauso from a thin-walled tubular blank which comprises upsetting the central longitudinal portion of the blank to increase the wall thickness thereof, slottin opposite sides of said portion, shrinking the end portions diametrically and simultaneously increasing the wall thickness thereof, spreading the edges of the slotted portion, stretching out the central part of the slotted ortion into transverse cylindrical form, fol ing over the edges into parallel annular flanges, upsetting the ends of the blank and forming flanges from said upset portion. v

10. The method of making an axle housing from a piece of tubing which comprises shrinking the central part of the tubing axially to increase the wall thickness and maintaining the diameter approximately unaffected, shrinking the ends at each side of the central part radiallyto increase the wall thickness thereof and expanding the diameter ,of the central part to provide an enlarged housing.

11. The method of preparing a thin walled tubular blank for the construction of an axle v casing which consists in endwise shrinkage of the blank alon its central portion to increase the wall t ickness of the same and forming diametrically dis d slots through said thickened walls of t e central portion.

In witness whereof I hereunto subscribe my name this 20th da of March, 1928.

' EU ENE B. CLARK.

tion of the blank to increase the wall thickness thereof, slotting opposite sides of said portion, shrinking the end ortions diametrically and simultaneously increasing the wall thickness thereof, spreading the edges of the slotted portion, stretching out the central part of the slotted portion-into transverse cylindrical form, and folding over the edges into parallel annular flanges.

9. The method of making an axle casing 

